In this episode, Walter finds more clues during sensory deprivation, helping the team locate September in his modest quarters. Meanwhile, Captain Windmark reports to his Commander with a request for a variance in their grand scheme: a requirement to eradicate the rogue Fringe Division science team.
This episode's glyphs spell:
Observers are featured in this episode.
A billboard in 'Anomaly XB-6783746' says "Smriti Isolation Tanks", foreshadowing Walter's use of the iconic sensory deprivation tank in 'The Boy Must Live'. The word "Smriti" is Sanskrit for "that which is remembered," and Walter went into the tank to help him extract a memory buried in his subconscious.
Windmark's interest in the Statue of Liberty snow globe in 'The Boy Must Live' foreshadows the return to Liberty Island in 'Liberty'.
In "The Boy Must Live" Walter told Peter that he remembered the first time Peter called him "Dad" in "The Man from the Other Side".
In "The Boy Must Live" the Observer revealed that Michael was his son and that his observations of Walter and Peter affected his feelings about his own son.
In "The Boy Must Live" Walter told Peter about memories he regained from the original timeline, including memories of Peter stepping into The Machine from "6:02 AM EST".
In "The Boy Must Live" September revealed that he was experimented on by other Observers and was biologically reverted to a purely human state as punishment for his interventions.